[PATCH bpf-next v8 1/4] libbpf: Extract prog load type check from libbpf_probe_bpf_helper

[Tao Chen <chen.dylane@linux.dev>]

Extract prog load type check part from libbpf_probe_bpf_helper
suggested by Andrii, which will be used in both
libbpf_probe_bpf_{helper, kfunc}.

Cc: Tao Chen <dylane.chen@didiglobal.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
 tools/lib/bpf/libbpf_probes.c | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 9dfbe7750f56..a48a557314f6 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -413,6 +413,23 @@ int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts)
 	return libbpf_err(ret);
 }
 
+static bool can_probe_prog_type(enum bpf_prog_type prog_type)
+{
+	/* we can't successfully load all prog types to check for BPF helper
+	 * and kfunc support.
+	 */
+	switch (prog_type) {
+	case BPF_PROG_TYPE_TRACING:
+	case BPF_PROG_TYPE_EXT:
+	case BPF_PROG_TYPE_LSM:
+	case BPF_PROG_TYPE_STRUCT_OPS:
+		return false;
+	default:
+		break;
+	}
+	return true;
+}
+
 int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helper_id,
 			    const void *opts)
 {
@@ -427,18 +444,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helpe
 	if (opts)
 		return libbpf_err(-EINVAL);
 
-	/* we can't successfully load all prog types to check for BPF helper
-	 * support, so bail out with -EOPNOTSUPP error
-	 */
-	switch (prog_type) {
-	case BPF_PROG_TYPE_TRACING:
-	case BPF_PROG_TYPE_EXT:
-	case BPF_PROG_TYPE_LSM:
-	case BPF_PROG_TYPE_STRUCT_OPS:
-		return -EOPNOTSUPP;
-	default:
-		break;
-	}
+	if (!can_probe_prog_type(prog_type))
+		return libbpf_err(-EOPNOTSUPP);
 
 	buf[0] = '\0';
 	ret = probe_prog_load(prog_type, insns, insn_cnt, buf, sizeof(buf));
-- 
2.43.0